Comparative Study of Pavement Rehabilitation Using Hot in-Place Recycling and Hot-Mix Asphalt: Performance Evaluation, Pavement Life Prediction, and Life Cycle Cost Analysis

The use of hot in-place recycling (HIR) for pavement surface rehabilitation has gained increasing attention in recent years with the aim of achieving sustainable pavement. For the purpose of cost saving and the consumption of 100% reclaimed asphalt pavement (RAP), an in-place HIR train has been developed to combine various units including preheating, milling, rejuvenating, and compacting. Compared with the conventional hot-mix asphalt (HMA) surface treatment, the HIR technique might result in different pavement performances as a result of the low mixing temperature and insufficient quality control. This study aimed to conduct a comparative analysis of pavement surface rehabilitation using HIR and HMA, including the performance evaluation, pavement life prediction, and life cycle cost analysis (LCCA). HIR and HMA mixes were collected from construction areas and the nearby asphalt plant, respectively. The loose mixes were reheated and compacted for performance testing, including dynamic modulus tests, Superpave IDT tests, and moisture susceptibility tests. The AASHTOWare Pavement ME Design software was adopted to predict the pavement life with two rehabilitation techniques, followed by the LCCA with regard to the prediction results. Test results showed that pavement surface rehabilitation with HIR achieves acceptable performance and economic benefits. However, the HIR mixes are brittle and more susceptible to cracking and, therefore, have shorter pavement service lives than HMA.